Alfredo carlo jaztni



A. c. JANNI? f REINFORCED-CONCRETE.VESSEL AND METHOD 0F BULDING THESAME. APPLICATION F|| .ED MAR. 21,1918.

Patented June 1, 1920.

UNITED STATES TENT OFFICE..

ALFREDO CARLO JANNI, OF NEW YORK, N. Y.

Application filed March 21, '1918.

T 0 all 4whom t may Concern.'

Be it known that I, ALFREDO CARLO JANNI,

a subject of the King of Italy, residing at N ew York, in the State ofNew York, have invented a certain Reinforced-Concrete Vessel and Methodof Building the Same, of which the following is a full, clear, and exactdescription, such as will enable others skilled in the art to make anduse the same.

.a My invention consists in the method and in the construction andarrangement of parts hereinafter described and particularly pointed outin the claims. In describing the various arrangements employed and shownin the drawings hereto attached and described in the specification I donot limit my invention to the precise mode, manner, form or constructionof vessel shown, or the several parts thereto, inasmuch as variousalterations may be made without changing the scope of my invention.

In the drawings, Figure 1 is a side view of my vessel with sectionsbroken out to illustrate the frame work; Fig. 2 is a half crosssectionof a midsliip portion looking at a bulkhead, partly broken out toillustrate the reinforcing thereof; and Fig. 3 is a crosssection throughone of the diagonals of the truss showing a truss member and slabs.

In the drawings, the numeral 4 designates the keelson, 5 and 6 the sidekeelsons and bilge stringer respectively, 7 the bottom truss chordelement, 8 the longitudinal lower deck beam, 9 the upper truss chordelement, 10 the upper deck, 11 the main deck, 12 the lower deck, 13 thecross beams, 14 collision bulkheads, 15 complete bulkheads, 16 stieningframe, 17 transverse deck beams, 18 stem, 19 rudder frame, and 20longitudinal bottom reinforcing members. Where vessels are of smallsize,it is not necessary to use stress members or bridging upon the bottom ofthe vessel, but in large vessels such construction may be found of greatbenefit. 21 designates truss, stress or bridging members forming a trussextending longitudinally on either side of the vessel. This truss, itwill be noted, extends substantially the whole length of the ship, in asubstantially vertical plane. Two of these trusses are used, beingrespectively placed along the sides of the vessel, and extending, in avertical direction, between the lower chord 7 and upper chord 9, Fig. 2.While I have shown for the purpose of illustration, these mem- Speccatonof Letters Patent.

Patented Julie 1, 1920.

serial No. 223,742.

bers in lattice or checkered arrangement, it is obvious that other formsof trusses may be used. 22 designates longitudinal deck beams; 23reinforcing bars as may be used in the various truss members, either forthe sides, bottom or decks of the vessel. 24 designates connectingstirrups; 25 bonding stirrups that extend from one slab 27 to the otherand are bent over the reinforcements 31 to be anchored in place; and 26bonding wires or stirrups that are bent around the reinforcements 23 andthat are bent over the stirrups which I prefer to use in supporting theplates, slabs or sections 27 to the truss or frame members 21. Thestirrups 24 extend about the reinforcing bars 23 and thence out of thetruss members 2l to become a part of the reinforcing in the plates 27that form the plating or skin of the vessel. rThe bonding wires 26likewise extend about the reinforcing bars 23 and are turned about thereinforcing wires 25 that lie buried in the plating or slabs. Thearrangement of bars, wires and stirrups may be changed to conform to theparticular requirement of vessels using my invention. The truss member21 and the plates overlying such member are preferably capable ofcertain limited movements with each other. The slabs 27 consist ofcement or concrete with wires or reinforcing bars embedded therein shownat-37 and preferably bonding wires or reinforcing extending through fromone slab to another as indicated at 25. The shape of these slabs may bevaried, but I prefer to use slabs of rectangular form. The plates, slabsor sections 27 preferably have their abutting margins overlying thetruss or frame members as shown in Fig. 3, but, if desired, the abuttingmargins need not be madeso as to overlie truss or frame members. That isto say, the slabs 27 may be made somewhat smaller, and of a size to fitin the spaces 21', whereby the outer faces of the slabs 27 will be flushwith the other faces of the truss diagonals 21.` rIhere is, however, anadvantage in having the abutting margins of the plates overlying thetruss or frame members, in that leakage is materially reduced thereby.2S designates a calking channel located between adjacent plates and 29is an open seam between such plates to the calkthe drawing, it isobvious that any aperture left between the plates and extending part Waytherethrough, Which is capable of receiving and holding calking, Willaccomplish the purpose desired. lhere desired, the recess betweenabutting plates, after the calking has been put in, may be closed orsealed by cement or other closure. 31 desig' I nates small bars in theplates 27; 32 continues outer marginal reinforces in bulkhead; 33continues inner marginal reinforces in bulkhead; 3l diagonal. cornerreinforces in bulkhead; 35 the ribs, and 36 the diaphragm of thebulkhead.

Concrete vessels have been constructed in two different Ways, either inthe manner of Wooden and steel vessels, or being' builtl upside down andbeing turned over in launching. When building my vessel in the mannersteel vessels are built, I prefer to construct the plating or skin andthereafter construct the frame Work or skeleton therein, but whenbuilding a vessel upside doivn, it is believed to be more economical toconstruct the frame Work or skeleton and upon it place the plates orskin. y

In steel ship construction, vert-ical steel frames are used With steelplating and the shearing stresses to which such vessels are subjectedare transmit-ted by the steel. plates stiiiened by the if "amc, lllhen,however, reinforced concrete is used in the construction of a vessela'dilliculty arises owing to the .fact that on account of the thinnessof the concrete skin of the vessel, it is unable to stand the enormousamount of shear to which the vessel .is almost continuously subjected inservice. Concrete cannot be depended upon in tension, on account ofeventual cracks which might appear even during the construction and doappear when a concreto vessel of the type heretofore constructed issubjected to the ordinary shearing stresses cncountered in actualservice. Such cracks, aside from causing leakage into the ships, permitthe sea-Water to reach and attack the reinforcing steel, which, if notgalvanized., rapidly expands as a consequence of rusting and so breaksthe concrete. Moreover, if the ship has not been properly designed as tothe arrangements of its structural units, these cracks gradually expandas a result of torsional and shearinr stresses. Therefore, concrete intension cannot be relied upon, but all chances for cracks must beeliminated. The important points to be remembered in building reinforcedconcrete vessels are l. The Working stresses of the concrete should beso low that the alternating stresses do not fatigue the material and theWorking stresses of the steel are determined as a consequence of thosein the concrete so that the two materials may act together;

2. The structural members should in general be preferably of such ageometrical shape that shear, at least in all vital points of the ship,is eliminated and substantially axial compression and tensionsubstituted therefor; I

3. The hull should be so constructed as to eliminate all cause ofaccidental cracks, shrinkage and the like; and

4:. The hull should be so designed that eventual cracks may be easilyrepaired.

In a ship, the stresses are subject to a great number of repetitions andin Vmost cases to a reversal also. Repetition of stresses is of minorimportance, While the reversal of stresses is of major importance asaifecting the crushing strength of concrete.

In order to relieve the skin of the vessel from these internal strains Ihave devised the hull of the vessel composed of a skeleton of trussconstruction, designed in such a Way that substantially the entireshear, at any point of the vessel, is taken up by the mem.- bers of thetruss skeleton, falling in that point, and substituted by substantiallyactual axial tension and compression along said elements; and by a slabconnected to this skeleton in such a manner that it cannot Work but incompression and tension, according to the elements of the truss withWhich it is connected; besides its withstanding the hydrostaticpressure.

Since this shear in a floating vessel may .occur also, on account ofrolling, when the position of its decks is not horizontal 'the system oftruss construction in many cases should he extended to the bottom of thevessel as Well as to one or more decks.

By means of the top and bottoni chord members, the system of diagonalsof the truss transmit their loads to a deck and bottom of the ship,which latter preferably are in turn part of the chord members.

It will be seen from F ig. l, showing the longitudinal section of theship, that shearing stresses in the concrete are practically eliminatedand that the shear occurring in the ship as a Whole is transformed intosubstantially axial compression and tension in structural membersspecially designed for that purpose.

The system of framing, which assists the hydrostatic pressure againstthe bottom of the ship, transmits its load chiefly to the two main sidetrusses.

In a ship of large size the arrangement of trusses shown With diagonalsmay be used on the bottom of the hull as Well as to the decks, as shownin Fig. 2 of thedrawings.

The longitudinal trusses preferably have for the upper and lower chordsa deck and the bottom of the vessel; and bulkheads may be provided toobtain additional reinforcement of such trusses. In Fig. 2 I have shownthe decking and bulkheads integrally east with the truss members orskeleton. Where a vessel will not be subjected to the stresses whichocean going vessels may meet with, it may be found desirable to cast thedecks or bulkheads separately from the truss members or skeleton.

The slabs or plates which constitute the skin of the hull are not reliedupon to assist any of the principal stresses of the ship but aredesigned merely to withstand the hydrostatic pressure and theirreinforcement is preferably laid in two ways parallel to the diagonal ofthe main truss. In constructing the slabs or plates, I prefer to embedwires, shown at 25, in abutting plates, which wires may also be passedabout a frame or truss member. These wires or reinforces permit alimited movement of the plates relative to each other or to the frame.It Ishould be noted that the sides of the vessel are non-monolithic;that is to say, there is no cementitious connection between the slabsand the truss elements 2l. The slabs are connected to the truss elementsby metallic reinforcing elements only. Such a connection, while nearlyrigid, is not quite rigid, due to the fact that the steel is morebendable and elastic than the concrete. There is then possible a verysmall relative movement between the slabs and the truss elements, thatis taken up-by a small deformation of the mentioned metallic reinforcingconnections. I have not shown slabs used for that portion of the sidingof the vessel above the upper deck because the amount of leakage wouldbe negligible through cracks in a monolithic construction for suchportion of the vessel. If desired, however, a similar arrangement ofskeleton and slabs may be used there.

It is obvious that the slabs may be cast at a distance from the skeletonand thereafter attached to the frame work in any suitable manner. Iprefer, however, to cast these slabs upon the skeleton itself and tocast the plates in such manner that a plate shall have contracted beforea plate abutting same is cast. Plates may be cast on the frame work nextto plates which were cast at a distance and later attached to the frame.In view of the fact that the skin of the vessel is formed of a number ofseparately formed concrete slabs, it is apparent that a crackoriginating in any one slab is strictly confined to that slab, and wouldnot progress beyond that slab' to weaken that part of the vessel, adisadvantage that is present in a monolithic structure.

Furthermore, a cracked slab may be readily broken out and a new oneinserted, or cast in place. This ease of repair is an importantadvantage arising from the nonmonolithic design. In the preferredarrangement of plates, it is thus seen that the bottom row of plates maybe cast at one time, then when they have contracted the neXt row ofplates may be cast, and so on until the uppermost row of plates shall becast.

The bulkheads are of reinforced concrete having marginal portionspreferably integral with a deck, the bottom of the vessel and the sidetrusses of the vessel. These marginal portions preferably havecontinuous outer marginal reinforces 32 and continuous inner marginalreinforces 33, together with diagonal corner reinforces 34. Within themarginal portion of the bulkhead are ribs 35 and the diaphragm 36,likewise constructed of reinforced cementitious material.

While I have shown a preferable arrangement of plates having betweenthem a calking recess extending partly through the plates, it is obviousthat I may extend the calking` recess between the plates as far as theunderlying truss member.

While for smaller vessels it may be desirable to have but one row ofplates between the upper and lower chord of the truss or skeleton, yet,in seagoing vessels it is highly desirable to have a plurality of platesbetween keelson and gunwale. Such an arrangement I have shown in Fig. 1of thc drawings.

Regardless of whether my reinforced concrete vessel is built inverted orin the usual manner in which wooden or steel ships are built, I arrangethe frame work or skeleton of my vessel in such a manner in relation tothe slabs, plating or skin, that the slabs, plating or skin practicallyserve merely to exclude the water from the vessel, not being relied uponas an element of strength of the vessel as a whole, while the frame workor skeleton takes care of the stresses to which the vessel is or may besubj ected.

I do not limit myself to the casting of the slabs or plating atdifferent times or in different tiers. There is an advantage resultingfrom allowing a slab to contract before the slabs next to it are cast,but frequently this separate casting of slabs is unnecessary. Likewise,I do not limit myself to a plurality of slabs between the gunwale andbottom for in smaller vessels this has been found not to be needed.

I claim as -my invention:

1. The hereinbefore described method of building a reinforced concretevessel which consists in constructing a frame work of diagonal trussmembers so arranged as to convert shear to which the vessel will besubjected into substantially aXial tension and compression, and uponsaid frame work independently forming slabs of cementitious material insuch a manner as to allow a certain limited movement of said slabsrelative to the frame work.

2. The hereinbefore described method of building a reinforced concretevessel which consists, first, in forming a frame work of` truss elementson the sides thereof and in forming upon portions of said truss elementsindependent slabs of cementitious material and when the said slabs ofcementitious material so formed have become contracted then formingadjacent slabs of cementitious material until the sides of the vesselshall be covered with said slabs.

3. In a concrete vessel, a truss forming part of the framing of thevessel, a series of independently7 formed matched concrete slabs carriedby said truss and forming the skin of the vessel, and interconnectingreinforcing elements mutually engaging adjacent slabs7 whereby anon-monolithic structure is formed.

4. In a concrete vessel, a longitudinally extending truss, a series ofindependently formed, matched concrete slabs carried by said truss andforming the skin of the Vessel, reinforcing elements connecting adjacentslabs, and further reinforcing elements connecting the respective slabsto adjacent truss elements.

5. In a reinforced concrete Vessel, a reinforced concrete trussextending longitudinally of the vessel, comprising substantiallyhorizontal upper and lower chords extending longitudinally of thevessel, the upper chord being located in proximity to an upper deck, thelower chord beinglocated approximately on a level with the keel of thevessel, reinforced concrete truss elements interconnecting the upper andlower chords and a plurality of separately formed concrete slabsattached to and supported by the reinforced concrete truss elements thatinterconnect said upper and lower chords, to form a non-monolithic skinfor the Vessel.

6. In a reinforced concrete Vessel, a concrete truss comprising upperand lower chords extending lengthwise of the vessel, the lower chordbeing approximately on a level with the keel, a plurality of diagonaltruss elements interconnecting the upper and lower chords, a pluralityof separately formed concrete slabs attached to and supported by thediagonal truss elements to form a non-monolithic skin for the Vessel,the slabs being connected to the diagonal truss elements thatinterconnect the upper and lower chords of the truss by reinforcingelements mutually embedded in individual slabs and adjacentcorresponding diagonal truss elements.

7. ln a reinforced concrete Vessel, a reinforced concrete trusscomprising upper and lower chords extending longitudinally of the vesseland along one side, the lower chord being approximately on a level withthe keel, a plurality of reinforced concrete truss elementsinterconnecting the upper and lower chords and a plurality of separatelyformed concrete slabs attached to and sup ported by the reinforcedconcrete truss elements that interconnect the upper and lower chords, toform a non-monolithic skin for the vessel, the several edges of saidslabs be ing arranged to overlie corresponding reinforced concrete trusselements.

ALFREDO CARL() JANNI.

